Coverage of the new lab-grown, 5-ounce burger patty, which was made from cow muscle stem cells, has been all over the news the past few days, since its taste-test in London on August 5th. Those few bites cost years of research and over $330,000 to make possible, and could lead to a more efficient and sustainable way of producing “meat.” This is important because meat production may not be able to keep up with our growing global population, and the mass management of livestock is almost undoubtedly negatively impacting the environment, public health, and the welfare of the animals themselves. But there’s still a lot of work to be done to make the process of growing meat in the lab feasible.
The muscle (or myoblast) stem cells used were taken harmlessly from living cows and then grown up and significantly expanded in a lab, to 20,000 strands of cells. These muscle stem cells can be coaxed to turn into different muscle cell types, such as myotubes or mature myofibrils. These cells appear to have worked well for making a meat-like burger, as tasters said the inside is “very close to meat,” although it, unsurprisingly, lacks some of the fattiness of a real beef burger. One way to include some fattiness would be by adding some adipose tissue derived stem cells, as the created of the burger, Mark J. Post, himself explains in a 2012 paper on the subject of culturing meat from stem cells.
But the issue of fat content may be minor compared to other hurdles that may need to be overcome to make the $330,000 patty-making process efficient enough to be feasible, and, not to mention, widely accepted by vegetarians. While muscle stem cells can be harmlessly collected, the process of growing the cells requires a liquid broth, called cell media, which usually has animal products such as fetal bovine serum (called FBS for short). FBS is collected from cow fetuses. It’s expensive and still requires slaughtering animals, costing around $250 and up to three cow fetuses for a liter of it. Serum replacements are being heavily explored, as Post himself discusses in his 2012 paper, but it’s hard to replace the “real thing” and make stem cells happy in an entirely synthetic environment. We still don’t understand all of their needs. (The best alternative would be having bacteria that synthetically make all of the components in the cell media. Growing cells in this way, without any animal products, is known as xeno-free culture.) Growing stem cells in general is an expensive process, as it requires large amounts of disposable plastic ware since it is vital to keep everything sterile.
So while the lab-grown burger is an impressive accomplishment, there is still a ways to go before it’s relatively efficient, widely accepted by vegetarians, and feasible for mass replacement of a real beef patty.
For further reading:
- Makiko Kitamura’s article “Brin’s $332,000 Lab-Grown Burger has Cake-Like Texture”
- The Washington Post’s video “Tasting the first test-tube burger”
- Mark J. Post’s article “Cultured meat from stem cells: Challenges and prospects”
- David A. Brindley et al.’s article “Peak serum: implications of serum supply for cell therapy manufacturing”
- Doris Lin’s article “Why Laboratory-Grown Meat is Not Vegan